This book has been designed for graduate students having Renewable Energy as a paper. The researchers who want to pursue their research on any aspect of sustainable architecture may get a systematic understanding of the subject. The book has been written in a very lucid language. It is conveniently divided into four chapters. The first chapter gives an introduction of the concept behind a sustainable structure. The second chapter deals with the actual design of a low energy dwelling for cold and cloudy climate. The third chapter deals with the financial aspects of a low energy building. For dissemination of any new technology the cost benefit analysis is a must. The epilogue emphasizes the key issues involved in designing and implementing low energy systems. The concept of energy conscious buildings needs to be adopted by Energy engineers, architects, civil, mechanical and illumination engineers, environmentalists, builders, township developers, planners and public at large.